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+# C ABI (proposal)
+
+## C datatypes
+| C Type      | Description              |     Size (B) |
+|:------------|:-------------------------|-------------:|
+| char        | Character / byte         |            8 |
+| short       | Short integer            |           16 |
+| int         | Integer                  |           32 |
+| long        | Long integer             |           64 |
+| long long   | Long long integer        |           64 |
+| T*          | Pointer                  |           64 |
+| float       | Single-precision float   |           32 |
+| double      | Double-precision float   |           64 |
+| long double | Extended-precision float | **Bikeshed** |
+
+## Registers
+| Register | ABI Name | Description    | Saver  |
+|:---------|:---------|:---------------|:-------|
+| `r0`     | —        | Zero register  | N/A    |
+| `r1`     | `ra`     | Return address | Caller |
+| `r2`     | `sp`     | Stack pointer  | Callee |
+| `r3`     | `tp`     | Thread pointer | N/A    |
+
+**TODO:** Parameters
+
+**TODO:** Saved
+
+**TODO:** Temp
+